So with that out of the way the biggest questions I have now are thus:

1st: do you have to sacrifice a weapon attack for an unarmed strike during your turn in order to trigger the +2 AC, or can you use your bonus action to punch and still get it?

the way I have read the unarmed stike seems like an extra tack-on to the attack, since you cannot unarmed strike as a bonus action before you attack, it says after you take an attack action, same with flury of blows. I'm not sure after someone told me one way, but I would like to know more about this key class feature.

2nd: what can this guy do that a fighter cannot, just in general? would I be better making a dex based fighter such as a battle master in order to do fancy things?

3rd: what feats can be taken to make a monk even better over a general stat increase, assuming varient humans are out of the question?